"Many people have assumed that jealousy is a social construction of human beings — or that it's an emotion specifically tied to sexual and romantic relationships," study co-author Christine Harris said in a news release. "Our results challenge these ideas, showing that animals besides ourselves display strong distress whenever a rival usurps a loved one's affection."

Harris, a psychologist who had been studying human jealousy, took on the project after watching her parents’ Border collies display what looked like jealousy.

The study also tested dogs’ reactions to a pail and a book and found little jealous behavior in response to those objects.

While the jealousy dogs experience may not be as complex as that of humans, it appears to be a basic form of the emotion.

"I think that it helps support the idea that we are not the only species that are wired to protect our bonded relationships from rivals," Harris said, according to "Today."

Pet owners on Twitter were not surprised.

Entering Gray Area, Study Says Dogs Can Be Green With Envy http://t.co/4DIkN2d15V -my cat's def jealous of my iPhone, I can tell u that much